3 stages of water cycle

Water cycle, which is also known as hydrological cycle, is the indefinite continuous movement of water of the earth in various interdependent states and in a cyclical form i.e moving through the earth's surface to the atmosphere and from the atmosphere back again to the earth.

The interdependent and continuous movement of all forms of water is what provide a bases for the concept of the hydrological or water cycle.

It describes the circulation and distribution of fresh water in all phases of matter on the earth and its atmosphere. It comprises :

1. Storages of water (cloud, interception - on leaf surfaces, surface storage - lakes, soil moisture and groundwater) 

2. Processes through which water moves from a phase and storage to another (precipitation, evapotranspiration, stem flow, infiltration, percolation, overland flow, substance flow and channel flow) 

3. Interrelationships between the processes and storages. 

4. Influence of man on these relationships. 

STAGES OF THE WATER CYCLE

Stage 1: Evapotranspiration. 

 

Water is transferred into the atmosphere from the earth surface as water vapour. This is the invisible gaseous state of water through evaporation from other water bodies like oceans, seas, rivers, lakes and land surfaces and through transpiration from plants. This combined process of transfer of water (evaporation and transpiration) is something referred to as evapotranspiration.

The rate of evaporation that occurs is a function of relative humidity of absorbed radiation and of air movement coupled with the nature of the surface.

Stage 2 : Condensation. 

With the transfer of water vapour to the atmosphere which condenses because of the prevailing low temperature, this results into condensation and eventually changes to form clouds.

The clouds formed in the atmosphere through condensation are heated up resulting into melting and then released back as precipitation i.e rain, snow, sleet, fog, falling over the land and seas (earth surface).

Stage 3 : Infiltration 

When the water is released back to the earth surface, it is distributed in various ways. Part of it is absorbed by plants, some immediately evaporate and thus return to the atmospheres, some sink into the soil and rocks through the process of infiltration forming ground water, while some act as surface run off directly off slopes to join streams and rivers and eventually reaching the seas and oceans.